Chase et al: Reproductive life history of anadromous Osmerus mordax in Massachusetts 
153 
42°40’N 
42°20’N 
42°0’N 
41°40’N 
71°20’W 71°0’W 70°40’W 70°20’W 70°0’W 
Figure 1 
Map of the study area in Massachusetts where rainbow smelt (Osmerus mor¬ 
dax) were sampled in 2004—2007 for analyses of their fecundity and repro¬ 
ductive life history. The black stars denote locations where fyke net sampling 
was conducted in 4 coastal rivers in the spring during spawning runs, and the 
black triangles denote the locations of tows completed in the winter during 
a trawl survey in marine waters. Sources for base map data: Esri, HERE, 
DeLorme, Mapmyindia. Base map data copyrighted OpenStreetMap contribu¬ 
tors and the GIS user community. 
coastal rivers from Cape Cod Bay to Plum Island Sound, 
Massachusetts, in the western Gulf of Maine (Fig. 1). 
Reproductive analyses 
Fecundity Rainbow smelt were collected and frozen 
whole during a trawl survey for Atlantic cod (Gadus 
morhua ) conducted by staff of the Massachusetts Divi¬ 
sion of Marine Fisheries aboard a commercial vessel in 
winter from 2004 through 2007, by using a standardized 
2-seam, high-rise bottom-trawl net with a 26.5-xn sweep, 
25.6 m headrope, 11.43-cm wing mesh, 7.62-cm codend 
mesh, and 5.08-cm mesh liner (Hoffman et al. 4,5 ). The 
meshes were diamond-shaped, and their measurements 
were taken when they were stretched. The target time for 
tows was 30 min, and the functional headrope height was 
4 Hoffman, W. S., S. J. Correia, and D. E. Pierce. 2012. Results 
of an industry-based survey for Gulf of Maine cod, November 
2003-May 2005. Mass. Div. Mar. Fish. Tech. Rep. TR-49, 37 p. 
[Available from website.] 
5 Hoffman, W. S., S. J. Correia, and D. E. Pierce. 2012. Results 
of an industry-based survey for Gulf of Maine cod, May 2006- 
December 2007. Mass. Div. Mar. Fish. Tech. Rep. TR-50, 45 p. 
[Available from website.] 
